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I have an Bosch AQ125-HX tankless water heater. Its been great and the most i have had to do is sand of the carbon residue occassionally. However I seem to be having a problem with it going cold during a shower several times lately. Any idea what might be causing this? Thanks in advance.

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The first thing I would do is to clean the unit out. The instructions for this is in your manual. Sometimes this is just a matter of things getting clogged up and limiting the flow. The flow sensor itself may also be plugged up making it more difficult to sense the flow of water. The process for cleaning these things is really quite simple. It does take a little time though. You will probably need a bucket, Two hoses, and some food grade white vinegar. If this does not work, just let us know. Good Luck!

Posted on Jun 30, 2008

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It's doubtful your water heater unit is the problem. There is simply no reason for it to only work on sinks unless some how the pipe size was drastically reduced coming out of the unit so sinks got plenty of hot water but the shower does not. Take a second look at the installation. The pipe should not be less than 1/2" coming out. If that's OK then consider a clog or valve problem.

May 18, 2015 | Titan SCR2 N-120 - 11.8 KW Tankless Water...

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Hello, I recently had a Rinnai tankless water heater installed. The old water heater was in the garage. The new tankless heater is installed outside, and is about 25 feet away from where the old one...

I agree with you. The foam insulation should only be on the Hot Water side. The cold water side doesn't make any difference, as that temperature rarely changes in California.

Hope this helped you AK, thanks for choosing FixYa.

Aug 10, 2011 | Air Conditioners

1 Answer

How do you change out an element on a Boshe AE115 tanless water heater

To provide you with more detailed information, I have included 3- links for the Bosch AE115 Tankless Water Heater. The first is the Owners Manual, which covers everything from Installation to Trouble- shooting and Repairing the heater. The second is an exploded view parts diagram. And, the third is a Service Bulletin on Removing & Replacing the Element Assembly.

I hope all of this helps you. Please let me know. Thanks.

May 12, 2011 | Air Conditioners

1 Answer

I have a Rheem Tankless Indoor RTG-74-PVN-2 that has been shutting off every now and then we would pull the power cord and wait for a few seconds and connect it back and wait for a seconds and push the...

Before calling service technician, open following link for Rheem troubleshooting resources:

Read manual for troubleshoot and yearly maintenance steps.

Repair most tankless problems yourself, same day, any brand for about $330

Upvote the help.
And take advantage of fixya expert assistance live.
For a price, expert works with you while you work on water heater or any do-it-yourself project.
Fixya is always less expensive than a service call.

May 08, 2011 | Air Conditioners

1 Answer

I have a customer who would like a Bosch AE-9.5 tankless water heater installed in the master bathroom. The master bath is located at the far end of the house & they are wasting a great deal of water...

In theory it sounds good, but I don't think it would function properly. Most folks install a low boy 20 or 25 gallon water heater near the master bath and use the home's cold water feed as the supply line. That way, the water for the master bath alone, will always remain hot.Of course this would involve some plumbing modifications.

Of course, the other less expensive solution, would be to insulate the hot water pipe(s) feeding the master bath, from the existing water heater. That way, there would be no heat loss in the pipe(s) so the water in the pipe would remain warm to hot all the time.

Either of the above solutions should heat things up for your customer.

Mar 07, 2011 | Air Conditioners

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While taking a shower the water will go cold and the display on the tankless water heater display will flash P1 and then the temperature setting.

If you're water supply comes from a well, you need to flush out the heating coils to remove the mineral scale. This needs to be done on a regular basis, if it is well water. If you're not using well water, something may wrong with the distribution valve(s). Check you Owners Manual and/or call a service technician for your brand of tankless heater.

Feb 07, 2011 | Air Conditioners

1 Answer

Our Rinnai C85 tankless water heater is used for radiant heating. During the heating season it will occasionally throw a "12" code and cut out. It will reset and run for several days. Technician...

Sorry to read about your problem, I hope this helps you out.

Ok your code 12 is a gas issue, or this listed below

Check that the gas is turned on at the water heater and gas meter. Check for obstructions in the flue outlet.
Ensure gas line, meter, and/or regulator is sized properly. Ensure gas type and pressure is correct. Bleed all air from gas lines. Ensure proper Rinnai venting material was installed. Ensure condensation collar was installed properly. Ensure vent length is within limits.
Verify dip switches are set properly. Ensure appliance is properly grounded. Disconnect keypad. Disconnect EZConnect or MSA controls to isolate the problem. Check power supply for loose connections.
Check power supply for proper voltage and voltage drops. Ensure flame rod wire is connected. Remove flame rod and check for carbon build-up; clean with sand paper or emery
cloth. Disconnect and reconnect all wiring harnesses on unit and PC board. Check all components for electrical short. Check gas solenoid valves for open or short circuits. Remove burner plate and inspect burner surface for condensation or debris.

your manometer levals should be around 3-4

if you are running other gas appliances, like pool heater

I tried to help you. Please help me and Rate/Vote on my response. We take the time to answer your question's. take the time to rate us.Thanks and good luck

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Jan 04, 2011 | Air Conditioners

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Hi, I have a Bosch WR250 tankless gas instant water heater. My problem is i am not getting a spark at the pilot when the hot water is turned on,the red light flashes after 10sec. I can here the...

Flashing red light indicates not enough pressure on the input cold water. I had this problem when the small filter was gummed up with ****. Remove the water input nut and inside is a small removable mesh filter. Also the hydro power unit that you hear whirring has a even finer mesh filter. It can also be cleaned out.

Jul 06, 2008 | Air Conditioners

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